Hydrogen-Atmosphere White Dwarfs Are Less Likely To Be Found with Wide-Binary Companions

Jeremy Heyl

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arXiv · 2407.17634

Hydrogen-Atmosphere White Dwarfs Are Less Likely To Be Found with Wide-Binary Companions

Jeremy Heyl

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Abstract

The fraction of white dwarfs found in wide binaries is estimated by cross referencing a catalogue of wide binaries with catalogues photometrically determined white-dwarf candidates and spectroscopically confirmed white dwarf stars. The wide-binary fraction of white dwarfs with hydrogen-dominated atmospheres is about 5%, but the fraction of white dwarfs with helium or carbon-dominated atmospheres is significantly larger. Using spectroscopic classifications, the binary fraction of DA white dwarfs is determined to be $0.063\pm0.002$ and for non-DA white dwarfs is larger at $0.080\pm0.004$.

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Jeremy Heyl. 2024-07-24. Hydrogen-Atmosphere White Dwarfs Are Less Likely To Be Found with Wide-Binary Companions. https://arxiv.org/abs/2407.17634

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